title: Caffeine intake and risk of basal cell and squamous cell carcinomas of the skin in an 11-year prospective study.
abstract: OBJECTIVE
  Caffeine may repair skin damage induced by excessive exposure to ultraviolet light. The purpose of this study was to investigate the association between caffeine intake and incidence of basal cell (BCC) and squamous cell carcinoma (SCC). We also assessed the associations between coffee consumption and incidence of these skin cancers.
  
  
  METHODS
  Caffeine intake and consumption of coffee were estimated from food frequency questionnaires assessed in 1992, 1994, and 1996 among 1,325 randomly selected adult residents of a subtropical Australian community. All histologically confirmed tumours of BCC and SCC occurring between 1997 and 2007 were recorded. Associations with BCC and SCC were assessed using Poisson and negative binomial regression models and were adjusted for confounders including skin type and indicators of past sun exposure.
  
  
  RESULTS
  There was no association between total caffeine intake and incidence of BCC or SCC. Participants with prior skin cancers, however, had a 25% lower risk of BCC if they were in the highest tertile of total caffeine intake (equivalent to daily consumption of four cups of regular coffee) compared with the lowest tertile (multivariable RR 0.75; 95% CI 0.57-0.97, P trend = 0.025). There was no dose-response relationship with SCC. Consumption of neither caffeinated nor decaffeinated coffee was associated with BCC or SCC.
  
  
  CONCLUSIONS
  Among people with prior skin cancers, a relatively high caffeine intake may help prevent subsequent BCC development. However, caffeine intake appears not to influence the risk of SCC.
authors.affiliation: Cancer and Population Studies Group, Queensland Institute of Medical Research, 300 Herston Road, Herston, Brisbane, QLD, 4006, Australia, Kyoko.Miura@qimr.edu.au.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Miura
authors.forename: Maria Celia B
authors.initials: MC
authors.lastname: Hughes
authors.forename: Adèle C
authors.initials: AC
authors.lastname: Green
authors.forename: Jolieke C
authors.initials: JC
authors.lastname: van der Pols
mesh_terms: D000328:Adult; D000368:Aged; D001315:Australia / Q000453:epidemiology; D002110:Caffeine / Q000008:administration & dosage*; D002280:Basal Cell Carcinoma / Q000453:epidemiology*; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology*; D003069:Coffee; D004032:Diet; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009790:Occupations; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012878:Skin Neoplasms / Q000453:epidemiology*; D012880:Skin Pigmentation; D012907:Smoking / Q000009:adverse effects; D013471:Sunburn; D013472:Sunlight / Q000009:adverse effects; D011795:Surveys and Questionnaires
chemical_list: D003069:Coffee; D002110:Caffeine